A prill is a small aggregate or globule of a material, most often a dry sphere, formed from a melted liquid through spray crystallization. Prilled is a term used in

mining Mining is the extraction of valuable minerals or other geological materials from the Earth, usually from an ore body, lode, vein, seam, reef, or placer deposit. The exploitation of these deposits for raw material is based on the economic ...

and

manufacturing Manufacturing is the creation or production of goods with the help of equipment, labor, machines, tools, and chemical or biological processing or formulation. It is the essence of secondary sector of the economy. The term may refer to ...

to refer to a product that has been pelletized.

ANFO ANFO ( ) (or AN/FO, for ammonium nitrate/fuel oil) is a widely used bulk industrial explosive. It consists of 94% porous prilled ammonium nitrate (NH4NO3) (AN), which acts as the oxidizing agent and absorbent for the fuel, and 6% number 2 fue ...

explosive typically comprises Ammonium Nitrate prills mixed with aluminium powder. The pellets are a neater, simpler form for handling, with reduced dust. The material to be prilled must be in a solid state at room temperature and a low-viscosity liquid when melted. Prills are formed by allowing drops of the melted prill substance to congeal or freeze in mid-air after being dripped from the top of a tall

prilling tower A shot tower is a tower designed for the production of small-diameter shot balls by free fall of molten lead, which is then caught in a water basin. The shot is primarily used for projectiles in shotguns, and for ballast, radiation shielding ...

. Certain agrochemicals such as

urea Urea, also known as carbamide, is an organic compound with chemical formula . This amide has two amino groups (–) joined by a carbonyl functional group (–C(=O)–). It is thus the simplest amide of carbamic acid. Urea serves an important ...

are often supplied in prilled form. Fertilizers (

ammonium nitrate Ammonium nitrate is a chemical compound with the chemical formula . It is a white crystalline salt consisting of ions of ammonium and nitrate. It is highly soluble in water and hygroscopic as a solid, although it does not form hydrates. It is ...

, NPK fertilizer) and some

detergent powder Laundry detergent is a type of detergent (cleaning agent) used for cleaning dirty laundry (clothes). Laundry detergent is manufactured in powder (washing powder) and liquid form. While powdered and liquid detergents hold roughly equal share ...

s are commonly manufactured as prills.Vasant Gowariker, V. N. Krishnamurthy, Sudha Gowariker, Manik Dhanorkar, Kalyani Paranjape (2009). ''The Fertilizer Encyclopedia''. John Wiley & Sons. . . However prilling of

and

has in recent years been replaced by

fluid bed granulation In physics, a fluid is a liquid, gas, or other material that continuously deforms (''flows'') under an applied shear stress, or external force. They have zero shear modulus, or, in simpler terms, are substances which cannot resist any shear ...

as this gives strong and more abrasion-resistant granules. Melted material may also be atomized and then allowed to form smaller prills that are useful in cosmetics, food, and animal feed.

References

Agricultural chemicals Metallurgy {{metallurgy-stub

See also

References